Save window position

MODDING.md

@@ -324,6 +324,7 @@ Stores general game settings and configuration; beyond individual characters.
 | `color` | Red, green and blue (0-1) of the menu color. |
 | `character_color` | `1` to use the character's color while playing. |
 | `width`, `height` | Window size. |
+| `x`, `y` | Window position. |
 | `last_character` | The character being played at exit, which the game continues on start. |
 | `console` | `1` enables the developer console (the grave key). |